Hybrid VTOL fixed-wing drone

ABSTRACT

A long-distance drone is disclosed having a canard body style with a main body, a left main wing, a right main wing, a left forewing, and a right forewing. The left forewing is attached to the main body forward of the left main wing, and the right forewing is attached to the main body forward of the right main wing. There is a left linear support connecting the left forewing to the left main wing, and a right linear support connecting the right forewing to the right main wing. A plurality of propellers are disposed on the left and the right linear supports.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to, and is a Divisional application of,U.S. patent Ser. No. 15/643,452, filed on Jul. 6, 2017, which is herebyincorporated by reference in its entirety.

Although incorporated by reference in its entirety, no arguments ordisclaimers made in the parent application apply to this divisionalapplication. Any disclaimer that may have occurred during theprosecution of the above-referenced application(s) is hereby expresslyrescinded. Consequently, the Patent Office is asked to review the newset of claims in view of all of the prior art of record and any searchthat the Office deems appropriate.

FIELD OF THE DISCLOSURE

The field of the disclosure is aircrafts in general and hybrid VTOLfixed-wing drones specifically.

BACKGROUND OF THE DISCLOSURE

Drones, whether manned or unmanned, have been proposed to conductvarious missions and functions. Their missions and functions, however,are often limited by the traveling range and endurance of the drone.There is a continuing need for a drone that is sufficiently efficient totravel longer distances.

There is also a continuing need for new ways of creating redundancy in adrone so that when one propeller fails, the drone may still function andcontinue to stay in the air.

All referenced patents, applications and literatures are incorporatedherein by reference in their entirety. Furthermore, where a definitionor use of a term in a reference, which is incorporated by referenceherein, is inconsistent or contrary to the definition of that termprovided herein, the definition of that term provided herein applies andthe definition of that term in the reference does not apply. Theembodiment may seek to satisfy one or more of the above-mentioneddesires. Although the present embodiment may obviate one or more of theabove-mentioned desires, it should be understood that some aspects ofthe embodiment might not necessarily obviate them.

BRIEF SUMMARY OF THE DISCLOSURE

In one aspect of the disclosed long-distance drone, it can have a canardbody style with a main body, a left main wing, a right main wing, a leftforewing, and a right forewing. The left forewing can be attached to themain body forward of the left main wing, and the right forewing can beattached to the main body forward of the right main wing.

There can be a left linear support spaced apart from said main bodyconnecting the left forewing to the left main wing.

There can also be a right linear support spaced apart from said mainbody connecting the right forewing to the right main wing.

In one aspect, there can be a first and a second propeller coupled tothe left linear support. In another aspect, there can be a third and afourth propeller coupled to the right linear support.

In further embodiments, there can be a fifth propeller coupled to theleft linear support, and a sixth propeller coupled to the right linearsupport.

In yet another embodiment, the first propeller, the second propeller,and the third propeller can be linearly arranged to parallel thelongitudinal axis of the main body, and the fourth propeller, the fifthpropeller, and the sixth propeller can be linearly arranged to parallelthe longitudinal axis of the main body.

The first propeller, the second propeller, and the third propeller canbe directly disposed on the left linear support, and the fourthpropeller, the fifth propeller, and the sixth propeller can be directlydisposed on the right linear support.

Contemplated drone can optionally have a push propeller disposed at aback end of the main body.

In another embodiment, instead of a push propeller, there can be aseventh propeller coupled to the main body and the seventh propeller hasa plane of motion that is perpendicular to a plane of motion of thefirst propeller.

Contemplated drone can further include a left vertical stabilizerdisposed on a back end of the left linear support, and a right verticalstabilizer disposed on a back end of the right linear support.

In some embodiments, the first propeller and the third propeller can bedisposed on a bottom side of the left linear support, while the secondpropeller can be disposed on a top side of the left linear support.

Likewise, the fourth propeller and the sixth propeller can be disposedon a bottom side of the right linear support, while the fifth propellercan be disposed on a top side of the right linear support.

In other embodiments, the first propeller and the second propeller aredisposed on opposing sides of the left linear support, and the fourthpropeller and the sixth propeller are disposed on opposing sides of theleft linear support.

Further contemplated is for the first propeller to have a first rangemotion with a first radius, and for the second propeller to have asecond range of motion with a second radius. In some embodiments, thedistance between the center of the first range of motion and the centerof the second range of motion can be less than twice the first radius.

In yet other embodiments, wherein from a top view, a range of motion ofthe first propeller visually overlaps with a range of motion of thesecond propeller.

In yet another embodiment, the first radius can be substantially thesame as the second radius.

Other embodiments of the disclosure include a fixed-wing drone having aleft main wing and a right main wing; a left linear alignment ofpropellers having a first propeller, a second propeller, and a thirdpropeller; a right linear alignment of propellers having a fourthpropeller, a fifth propeller, and a sixth propeller. In someembodiments, the left linear alignment is parallel to the right linearalignment.

Contemplated first propeller, second propeller, and the third propellercan be directly disposed linearly in a straight line on the left linearsupport, and the straight line can be parallel to a longitudinal axis ofthe main body.

There is also contemplated a method of improving stability, and/ordurability, and or redundancy in a hybrid fixed-wing VTOL drone. In oneembodiment, the method can include connecting a left main wing to a leftcanard forewing with a left linear support. Also, the method can includeconnecting a right main wing to a right canard forewing with a rightlinear support.

In some embodiments, the left and right linear supports can counteractagainst a twisting force applied to the main body of the drone duringflight.

Contemplated method can include a step of arranging a spatialrelationship between a center of gravity of the drone and said at leastthree propellers disposed on each of the left and right linear support,such that when any one of said propellers malfunctions, the drone mayremain functioning by simply shutting down one other said propellers.

Various objects, features, aspects and advantages of the presentembodiment will become more apparent from the following detaileddescription of embodiments of the embodiment, along with theaccompanying drawings in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS

It should be noted that the drawing figures may be in simplified formand might not be to precise scale. In reference to the disclosureherein, for purposes of convenience and clarity only, directional termssuch as top, bottom, left, right, up, down, over, above, below, beneath,rear, front, distal, and proximal are used with respect to theaccompanying drawings. Such directional terms should not be construed tolimit the scope of the embodiment in any manner.

FIG. 1 is a top front perspective view of an embodiment of thecontemplated drone utilizing a canard design having two parallel linearsupports to connect the forewings with the main wings.

FIG. 2 is a top perspective view of an embodiment of the contemplateddrone.

FIG. 3 is a bottom perspective view of an embodiment of the contemplateddrone.

FIG. 4 is a top view of one embodiment of the contemplated drone.

FIG. 5 is a bottom view of one embodiment of the contemplated drone.

FIG. 6 is a direct frontal view of one embodiment of the contemplateddrone.

FIG. 7 is direct rear view of one embodiment of the contemplated drone.

FIG. 8 is a right side view of one embodiment of the contemplated drone.

FIG. 9 is a top view of another aspect of the contemplated drone,illustrating spatial relationships of the propellers to each other, andexplains the center of gravity of the drone.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The drone and its various aspects can now be better understood byturning to the following detailed description of the embodiments, whichare presented as illustrated examples of the embodiment defined in theclaims. It is expressly understood that the embodiment as defined by theclaims may be broader than the illustrated embodiments described below.

Many alterations and modifications may be made by those having ordinaryskill in the art without departing from the spirit and scope of theembodiment. Therefore, it must be understood that the illustratedembodiment has been set forth only for the purposes of example and thatit should not be taken as limiting the embodiment as defined by thefollowing claims. For example, notwithstanding the fact that theelements of a claim are set forth below in a certain combination, itmust be expressly understood that the embodiment includes othercombinations of fewer, more or different elements, which are disclosedherein even when not initially claimed in such combinations.

The words used in this specification to describe the embodiment and itsvarious embodiments are to be understood not only in the sense of theircommonly defined meanings, but to include by special definition in thisspecification structure, material or acts beyond the scope of thecommonly defined meanings. Thus if an element can be understood in thecontext of this specification as including more than one meaning, thenits use in a claim must be understood as being generic to all possiblemeanings supported by the specification and by the word itself.

The definitions of the words or elements of the following claimstherefore include not only the combination of elements which areliterally set forth, but all equivalent structure, material or acts forperforming substantially the same function in substantially the same wayto obtain substantially the same result. In this sense it is thereforecontemplated that an equivalent substitution of two or more elements maybe made for any one of the elements in the claims below or that a singleelement may be substituted for two or more elements in a claim. Althoughelements may be described above as acting in certain combinations andeven initially claimed as such, it is to be expressly understood thatone or more elements from a claimed combination can in some cases beexcised from the combination and that the claimed combination may bedirected to a subcombination or variation of a subcombination.

As used herein, the terms “failure” and “malfunction” in conjunctionwith a propeller refer to a condition where the propeller cease tofunction properly as intended by its manufacturer due to reasons outsideof its control. For example, a propeller may fail or malfunction when itis damaged by an outside force. Propellers in a drone are known to bedamaged when it collides with a bird, a tree, or a building. A propellermay also fail or malfunction when its mechanical or electrical amaterial component experience a break down. Also, a propeller may failor malfunction when its power supply or fuel supply ceases to supplyenergy to the propeller when such supply of energy is expected.

As used herein, the term “center of gravity” in conjunction with thedrone refers to a center of gravity in consideration of the total weightof the drone including all of its components, fuel (if any), and itspayload. For example, if the drone is contemplate to carry cargo orhuman, the weight of the cargo and/or human would be part of thecalculation in designing where the center of gravity should be.

As used herein, the term “range of motion” in conjunction with thepropeller refers to a circular area having a radius equal to the lengthof the propeller's blade. Since the blade of the propeller is designedto rotate either in a clockwise or counter-clockwise along a plane, therange of motion can also be described as a circular area along a plane.

As used herein, the term “overlap” in conjunction with the range ofmotions of propellers refers to a visual appearance that two circularareas have certain portions touching each other, but does not meanphysical touching. That is, when two ranges of motions “overlap,” theydo not mean physically overlapping each other. When two ranges ofmotions “overlap,” they merely appear to be in each other's space whenlooking from a particular angle. This overlaps may or may notnecessarily create interference in fluid dynamics and aerodynamics ofthe two adjacent propellers.

As used herein, the term “hybrid” in conjunction with fixed-wing VTOLdrone design refers to the classification of aircraft type, and does notrefer to its power train. In the disclosure here, the term “hybrid”refers to the fact that the contemplated drone is a fixed-wing aircraftand at the same time has propellers so that the drone can verticallytake-off and land (VTOL). In terms of power train, the contemplatedembodiments can use entirely electric power train, a fuel-powered powertrain, a combination of both, or any other known or yet to be knownpower train technology.

As used herein, the term “drone” refers to any manned or unmannedaircraft, of various sizes. For example, contemplated drones asdisclosed herein can have a wingspan of less than 0.5 meter, and canhave a cabin space sufficiently large to seat passenger(s). The term“drone” as used herein can or cannot be limited to unmanned aerialvehicles (UAV).

As used herein, the term “vertical” in conjunction with a stabilizerrefers to any angle. In one embodiment, it is at a 90 degree angle,perpendicular to the horizontal plane of the main wings. In otherembodiments, it can be at a tilted angle.

The inventor has discovered a novel hybrid VTOL fixed-wing drone designthat can drastically improve at least one of the followingcharacteristics in a drone: efficiency, durability, travel distance, andredundancy.

Referring now to FIG. 1, FIG. 1 generally depicts the basic structure ofa hybrid VTOL Fixed-wing drone 100 in accordance with one aspect of thedisclosure.

Drone 100 is contemplated to have a main body 110, two forewings 111,112 attached to the front end of the main body 110. There are two mainwings 113, 114 attached to the main body towards the rear of the mainbody 110. This is a typical canard design where two smaller forewingsare placed forward to two larger main wings.

Main body 110 can have an aerodynamic design and may optionally have acabin sufficiently large to seat human passenger(s) or cargo. In theexemplar drone 100 as shown in the drawing figures, what appears to be awindshield 118 may or may not be an actual functional windshield 118,depending on whether the particular embodiment has a passenger cabin.

There can be two main wings 113 and 114 attached to the rear portion ofthe main body 110. In some embodiments, terminal ends of each of themain wings 113 and 114 may have a vertical stabilizer 115, 116.

Forewings 111 and 112 can be attached to the front end of the main body110. Forewings 111, 112 are shorter than the main wings 113, 114.

There can be a left and a right linear supports 120, 121, each of whichphysically connects a forewing 111, 112 to the main wings 113, 114. Inone aspect of the contemplated embodiment, the linear supports 120, 121are fixed near the terminal ends of each perspective forewings 111, 112.In one embodiment, the linear supports 120, 121 can be fixedly attacheda location on the forewings 111, 112 that is distal to the middle pointbetween the tip of the forewings 111, 112 and the main body 110. In yetanother embodiment, the linear supports 120, 121 can be fixedly attachedto anywhere along the length of the forewings 111, 112. Although theexemplar linear supports 120, 121 shown in FIG. 1 are attached to theundersides of the forewings 111, 112, other embodiments may have thelinear supports 120, 121 attached to the upper side of the forewings111, 112.

The contemplated linear supports 120, 121 can be made of suitablematerials to withstand the physical demands of flying, and can resistcontortion. Such materials include natural and synthetic polymers,various metals and metal alloys, naturally occurring materials, textilefibers, glass and ceramic materials, and all reasonable combinationsthereof.

The straight linear supports 120, 121 can provide structural integrityto the drone 100 by minimizing a contortion force applied to the mainbody 110 by the up and down movement of the main wings 113, 114 and theforewings 111, 112 during flight.

The linear supports 120, 121 can have a straight body and can beparallel to the longitudinal axis of the main body 110. As shown in thefrontal view of FIG. 6, the straight body configuration allows minimumaerodynamic obstruction during flight. The linear supports 120, 121 canhave a thickness that is no thicker than the thickest part of the mainwings 113, 114. The linear supports 120, 121 can have a cross-sectionalshape that is circular, oval, square, rectangular, or any other suitableshape.

In other contemplated embodiments (not shown), the linear supports 120,121 can have a curvature or other angles besides being straight.

The left and right linear supports 120, 121 can have a suitable lengthto connect forewings 111, 112 to the main wings 113, 114. In theembodiment as shown in FIG. 3, the left and right linear supports 120,121 are attached to the underside of the forewings 111, 112.

In the exemplar drone 100 shown in the drawing figures, the left and theright linear supports 120, 121 each can have a vertical stabilizer 125,126 disposed on the top of its rear terminal end. In one embodiment, thevertical stabilizers 125, 126 are at a 90 degree angle, perpendicular tothe horizontal plane of the main wings. In other embodiments, thesevertical stabilizers 125, 126 can be at a tilted angle.

It should be understood that the above-described angles are exemplaryand any other angles can be adopted in various embodiments of thisdisclosure.

Referring now to FIG. 3, there can optionally be rotors and propellersdisposed on each of the linear supports 120 and 121 to provide verticaltake-off and landing capabilities to the drone 100. Various numbers ofpropellers are contemplated. In the embodiments shown in the figures,each linear support 120, 121 has three propellers. Left linear support120 can have a propeller 131 disposed at the front terminal end of thelinear support 120, on the underside of the left forewing 111, facingdownwards. Left linear support 120 can have another propeller 132disposed on top of the linear support 120 at a location in between theforewing 111 and the main wing 113, facing upwards. Left linear support120 can have yet another propeller 133 disposed at the bottom of thelinear support 120 near a rear terminal end, facing downwards.

Similarly on the right side of the drone 100, right linear support 121can have a propeller 134 disposed at the front terminal end of the rightlinear support 121, on the underside of the right forewing 112, facingdownwards. Right linear support 121 can have another propeller 135disposed on top of the right linear support 121 at a location in betweenthe forewing 112 and the main wing 114, facing upwards. Right linearsupport 121 can have yet another propeller 136 disposed at the bottom ofthe right linear support 121 near a rear terminal end, facing downwards.

Each of the propellers 131, 132, 133, 134, 135, 136 shown in the drawingfigures has two blades. In some embodiments, propellers 131, 132, 133,134, 135, 136 can lock into a longitudinal position (as shown in FIGS.1-4) during high speed flying when these propellers 131, 132, 133, 134,135, 136 are not necessary to keep the drone 100 in air. By lockingthese propellers into a longitudinal position parallel to the directionof the flight, aerodynamic is improved, as opposed to not locking themor keeping them spinning.

As those of ordinary skill in the art will recognize, the propellers131, 132, 133, 134, 135, 136 may readily be modified as dictated by theaesthetic or functional needs of particular applications. For example,each of all or some of the propellers 131, 132, 133, 134, 135, 136 canhave 2-blades, 3-blades, 4-blades, or any other known types of blades.

As to the rotors that drive the propellers 131, 132, 133, 134, 135, 136,to maintain an aerodynamic profile, rotors should have as low a profileas possible. It is important to appreciate that although the presentembodiment is particularly well suited for use by implementing alow-profile rotor, it should be understood that other types of rotor orcombinations of different types of rotors can be used to perform thatsame function as the low-profile rotors.

As shown in FIG. 6, the contemplated rotors can be disposed within thelinear supports 120, 121 and do not bulge out or extend beyond theaerodynamic contour of the linear supports 120, 121. Even the propellers131, 132, 133, 134, 135, 136 can have a low-profile and can be disposedclosely to the linear supports 120, 121 so that when the propellers 131,132, 133, 134, 135, 136 are locked in a longitudinal position (as shownin FIG. 6) during high speed flying, an improved aerodynamic profile ispresent.

In one embodiment, the lowest portion of the propellers 131, 132, 133,134, 135, 136 do not extend beyond the lowest part of the main body 110.In another embodiment, the highest portion of the propellers 131, 132,133, 134, 135, 136 do not extend beyond the highest part of the mainbody 110. As shown in FIG. 6, form a frontal view, the distance betweenthe highest points of the propellers 131, 132, 133, 134, 135, 136 to thelowest point of the propellers 131, 132, 133, 134, 135, 136 issubstantially equal to the thickest part of the main wings 113, 114.

In yet another contemplated embodiment, a novel feature includesarranging multiple rotors/propellers in only two parallel columns suchthat from a frontal view, these multiple rotor/propellers create onlytwo points 191, 192 of air disturbance (see FIG. 6). This is importantbecause this design drastically improve the aerodynamic profile of amulticopter drone, or a VTOL drone.

FIG. 8 illustrates one embodiment of how the six propellers 131, 132,133, 134, 135, 136 can be arranged. In this embodiment, the sixpropellers 131, 132, 133, 134, 135, 136 are arranged in two columnsparallel to each other. Each column can be parallel to the longitudinalaxis of the main body 110. Known multi-copter drones arrange theirpropellers in an evenly spaced array to encircle around the center ofgravity, because evenly spaced array in a circle provides the beststability and redundancy. When one propeller in such prior artmulti-copter drone fails, the prior art multi-copter simply turns offanother propeller on the opposite end of the circular array so the restof the working propellers are balanced to keep the drone in the air. Inthe embodiment shown in FIGS. 1-5, the six propellers 131, 132, 133,134, 135, 136 are not evenly spaced apart from an adjacent propeller. Byhaving the six propellers 131, 132, 133, 134, 135, 136 arranged in twoparallel columns, drag is minimized because the frontal profiles of allsix propellers 131, 132, 133, 134, 135, 136 would only equal to thefrontal profile of about two such propellers (see FIGS. 6 and 7).

It should be particularly appreciated that although the drawing figuresonly show six propellers 131, 132, 133, 134, 135, 136, any even numbersof propellers can be arranged in two parallel columns. In oneembodiment, the drone 100 can have two parallel columns of propellers,each column having two propellers. In another embodiment, the drone 100can have two parallel columns of propellers, each column having fourpropellers. In yet another embodiment, the drone 100 can have twoparallel columns of propellers, each column having five propellers.

This plurality of propellers 131, 132, 133, 134, 135, 136 may bedisposed on various locations along the length of the linear supports120, 121.

In one embodiment as shown in FIGS. 4 and 5, linear supports 120, 121each has a rear terminal end that extends rearward beyond the rear edgeof the main wings 113, 114. By extending its rear terminal end beyondthe rear edge of the main wings 113, 114, the linear supports 120, 121in the exemplar embodiment can have propellers 133, 136 disposed on thetheir terminal end without having the main wings 113, 114 in the way ofairflow during vertical takeoff and landing. As shown in FIG. 9, the twocircles surrounding propellers 133, 136 represent the range of motionfor their respective blades. Both circles do not overlap with the mainwings 113, 114.

In the embodiments shown in the drawing figures, contemplated linearsupports 120, 121 do not extend forward beyond the frontal edge of theforewings 111, 112. The embodiment shown in FIG. 3 has both linearsupports 120, 121 terminate right underneath the forewings 111, 112. Theterminal ends of the linear supports 120, 121 can each form a verticalledge 122, 123.

In another embodiment (not shown), contemplated linear supports 120, 121may each extend beyond the frontal edge of the forewings 111, 112. Inthat way, the two front-most propellers 131, 134 can operate withoutbeing interfered by the forewings 111, 112 being in the way of airflow.

In the embodiment shown in FIG. 9, high efficiency can be achieved bykeeping the main body 110 and the linear supports 120, 121 reasonablyshort, thereby keeping the total weight of the drone relatively low.Instead of using smaller propellers 131, 132, 134, 135 in the first tworows of propeller arrangement so these two rows of propellers do notinterfere with each other by overlapping their range motion, thisembodiment can have the first rows' range of motion 164 overlap thesecond row's range of motion 165. In the embodiment of FIG. 9, eachpropeller in the first row can have a radius R4. Each propeller in thesecond row can have a radius R5. Each propeller in the last row can havea radius R6.

Although the propellers with different length of blades (thereby adifferent range of motion radius) can be utilized, the embodiment inFIG. 9 has all six propellers 131, 132, 133, 134, 135, 136 having thesame radius. In this embodiment, the distance between the centerrotating axle 154 of propeller 134 to the center rotating axle 155 ofpropeller 135 is less than twice the radius R4.

From a top view, the ranges of motions 164, 165 appear to overlap eachother partially. Their respective propeller blade, however, do notphysically make contact with each other because these two propellers134, 135 are disposed on opposite sides of the same linear support 121.All six propellers 131, 132, 133, 134, 135, 136 blow air in a downwardfashion.

In one aspect of the disclosure, the contemplated drone 100 can have apush propeller 137 disposed on the rear end of the main body 110. Thepush propeller 137 has a spinning axle that is perpendicular to thespinning axles of propellers 131, 132, 133, 134, 135, 136. During highspeed flight, the push propellers 137 is instrumental moving the drone100, whereas all six propellers 131, 132, 133, 134, 135, 136 are lockedand not rotating as described above.

Drone 100 can be equipped with other accessories, such as a camera 140to conduct aerial surveillance and other date collection. Camera 140 canbe disposed at any other position on the drone 100.

Contemplated drone 100 can optionally have one or more air diffusersdisposed on the underside of the drone. As shown in FIG. 3, one airdiffuser 142 can be disposed on the rear bottom end of the main body110. The diffuser 142 can be a shaped section of the main body'sunderbody. In other embodiments, the air diffuser 142 may act as adeturbulator.

One aspect of the instant disclosure includes a contemplated method toarrange a spatial relationship between a center of gravity of a droneand at least three propellers disposed on each of the left and rightside of the drone, whether or not these propellers are disposed on thelinear supports. In some embodiments, these propellers are arranged inpairs, each pair being equal-distant to each other forming two parallelarrays. The intended objective is to keep the drone 100 reasonably lightweight, to keep the drone aerodynamically enhanced, to have sufficientpower to vertically takeoff without resorting to the biggest andstrongest rotors, and to have a build-in redundancy such that when anyone of the six or more propellers malfunctions, the drone may remainfunctioning by simply shutting down one other said propellers.

For example, when propeller 131 fails, the drone can turn off propeller136 to still keep the drone balanced; when propeller 132 fails, thedrone can turn off propeller 135 to still keep the drone balanced; whenpropeller 133 fails, the drone can turn off propeller 134 to still keepthe drone balanced; and vise versa.

As illustrated in FIG. 6, the spatial arrangement of the propellers 131,132, 133, 134, 135, 136 between each other and to the center of gravityof the drone can be done by the following method. In one example,consider that each of the six propellers 131, 132, 133, 134, 135, 136have the same output of 1 kg. Propellers 131 and 134 would have a centerof lift force (2 kg) at point W (line A), which is a point equal-distantto the center of propeller 131 and propeller 134. Propellers 131, 132,134 and 135 would have a center of lift force (4 kg) at point X (lineB), which is a point equal-distant to the center of propellers 131, 132,134 and 135. Propellers 132, 133, 135 and 136 would have a center oflift force (4 kg) at point Y (line C), which is a point equal-distant tothe center of propellers 132, 133, 135 and 136. Propellers 133 and 136would have a center of lift force (2 kg) at point Z (line D), which is apoint equal-distant to the center of propellers 133 and 136. Thecontemplated center of gravity for the entire drone 100 can be line CGwhich is two third the distance from line A to line C, which is also onethird the distance from line B to line D.

Another aspect of the instant disclosure is a method of making hybridVTOL fixed-wing drones lighter while providing it with sufficientstructure and powertrain needs to maintain long-distance flying and/orhigh speed flying. Longer main body would mean heavier body that causesthe flight time to decrease unless larger powertrain and power source isprovided, which in turn also cause the drone to be heavier and lessaerodynamic.

In yet another aspect of the disclosure, a novel way of arrangingmultiple propellers in a hybrid VTOL fixed-wing drone includes thatpropellers to not stack on top of another propeller. In the illustratedembodiments, six propellers 131, 132, 133, 134, 135, 136 arehorizontally spaced part from each other, and there can be no stackingof propellers.

In one contemplated method, the first row of propellers are caused tooverlap in their range of motion with the second row of propellers whenlooking from a top view. In another contemplated method, the first rowof propellers 131, 134 are disposed near or at the bottom side of thecanard forewings 111, 112.

Contemplated fixed-wing drones having the disclosed features or designedby the disclosed methods can expect to have a continuous flight time ofat least eight hours when using an electric powertrain, and 24-hourswhen using a hybrid (fuel-electric) powertrain.

The above disclosed embodiments can be made of all known suitablenatural or synthetic materials or a mixture of materials. Additionally,it should be appreciated that the materials contemplated herein may bederivatized in numerous manners.

Although all of the above inventive features discussed are discussed inconjunction with a canard body style in an aircraft, all of the featuresdiscussed are also contemplated to be implemented on any otherfixed-wing aircraft body styles. These features specifically includes,but are not limited to: arrangement of multiple rotors/propellers inonly two parallel columns; arrangement of multiple rotors/propellersthat occupy only two points of disturbance from a frontal view; havingtwo parallel linear supports to physically connect wings in the front towings in the back; overlapping propellers' ranges of motion to decreasethe length of the main body of the aircraft; disposing adjacentpropellers on opposite sides of the drone (e.g., one disposed on top,the other disposed on the bottom of the drone); utilizing low-profilerotors that are no thicker than the thickest part of a main wing;utilizing low-profile propeller blades that does not extendsubstantially beyond the highest part of the main wing; and utilizinglow-profile propeller blades that does not extend substantially beyondthe lowest part of the main wing.

Another way of describing this novel method of improving an aerodynamicprofile of a drone is to entirely enclose low-profile rotors for each ofthe at least three propellers disposed on each linear support 120, 121.In this way, the linear array of these three propellers can have acombined frontal projection that substantially equals to a crosssectional area of each linear support 120, 121.

Additionally, although flaps, ailerons, rudders, and elevators are notspecifically discussed in this disclosure, each of them can be used inany of the disclosed embodiments.

Thus, specific embodiments and applications of a hybrid VTOL Fixed-WingDrone have been disclosed. It should be apparent, however, to thoseskilled in the art that many more modifications besides those alreadydescribed are possible without departing from the disclosed conceptsherein. The embodiment, therefore, is not to be restricted except in thespirit of the appended claims. Moreover, in interpreting both thespecification and the claims, all terms should be interpreted in thebroadest possible manner consistent with the context. In particular, theterms “comprises” and “comprising” should be interpreted as referring toelements, components, or steps in a non-exclusive manner, indicatingthat the referenced elements, components, or steps may be present, orutilized, or combined with other elements, components, or steps that arenot expressly referenced. Insubstantial changes from the claimed subjectmatter as viewed by a person with ordinary skill in the art, now knownor later devised, are expressly contemplated as being equivalent withinthe scope of the claims. Therefore, obvious substitutions now or laterknown to one with ordinary skill in the art are defined to be within thescope of the defined elements. The claims are thus to be understood toinclude what is specifically illustrated and described above, what isconceptually equivalent, what can be obviously substituted and also whatessentially incorporates the essential idea of the embodiment. Inaddition, where the specification and claims refer to at least one ofsomething selected from the group consisting of A, B, C . . . and N, thetext should be interpreted as requiring only one element from the group,not A plus N, or B plus N, etc.

What is claimed is:
 1. A method of improving stability, robustness,endurance and durability of a VTOL fixed-wing drone, said methodcomprising: having a left hind wing, a right hind wing, a left forewing,and a right forewing, all of which being attached to a fuselage of theVTOL drone; providing no more than two linear supports to minimize drag,said two linear supports consists of a left linear support and a rightlinear support; connecting the left hind wing with the left forewingwith the left linear support to minimize a contortion force applied tothe fuselage during flight; connecting the right hind wing with theright forewing with the right linear support to minimize the contortionforce applied to the fuselage during flight; having a first plurality oflifting propellers entirely disposed on an outside of the left linearsupport; having a second plurality of lifting propellers entirelydisposed on an outside of the right linear support; locking the firstplurality and second plurality of lifting propellers in a fixed positionduring flight while the first plurality and second plurality of liftingpropellers remain entirely disposed on the outside of the left and rightlinear supports, respectively; wherein the left and right linearsupports are spaced apart from the fuselage and provide enhanced overallintegrity of the drone during flight; and wherein one of the at leastthree lifting propellers disposed entirely on the outside of the leftlinear support is disposed on a top side of the left linear support, andanother one of the at least three lifting propellers disposed entirelyon the outside of the left linear support is disposed on a bottom sideof the left linear support.
 2. The method as recited in claim 1, whereinthe first plurality of lifting propellers is at least three propellersdisposed in a linear array and the second plurality of liftingpropellers is at least three propellers disposed in a linear array. 3.The method as recited in claim 2, wherein the linear array on the leftlinear support parallels with the linear array on the right linearsupport.
 4. The method as recited in claim 3, wherein the left and rightforewings and the left and right hind wings have no movable flightcontrol surfaces.
 5. The method as recited in claim 3, wherein at leasttwo of the first plurality of lifting propellers partially overlap intheir range of movement from a top view.
 6. The method as recited inclaim 3, wherein the left hind wing and the right hind wing are the rearmost horizontal wings in the drone.
 7. The method as recited in claim 3,wherein the left forewing is shorter than the left hind wing.
 8. Themethod as recited in claim 3, placing a center of gravity of the droneon a center longitudinal location of the fuselage, wherein the center ofgravity is located at two third of a distance from a point A which isdefined as a center of lift force between a foremost lift propeller onthe left linear support and a foremost propeller on the right linearsupport to a point C which is defined as a center of lift force betweena rearmost two lift propellers on the left linear support and a rearmosttwo lift propellers on the right linear support.
 9. The method asrecited in claim 3, wherein said center of gravity is located at onethird of a distance from a point B which is defined as a center of liftforce between a foremost two lift propellers on the left linear supportand a foremost two lift propellers on the right linear support to apoint D which is defined as a center of lift force between a rear mostlift propeller on the left linear support and a rearmost propeller onthe right linear support.
 10. A method of improving stability of a VTOLfixed-wing drone, said method comprising: having a left hind wing, aright hind wing, a left forewing, and a right forewing, all of whichbeing attached to a fuselage of the drone; providing no more than twolinear supports to minimize drag, said two linear supports consists of aleft linear support and a right linear support; connecting the left hindwing with the left forewing with the left linear support to minimize acontortion force applied to the fuselage during flight; connecting theright hind wing with the right forewing with the right linear support tominimize the contortion force applied to the fuselage during flight;having at least three lifting propellers entirely disposed on theoutside of the left linear support; having at least three liftingpropellers entirely disposed on the outside of the right linear support;locking the at least three lifting propellers of the left linear supportand the at least three lifting propellers of the right linear support ina fixed position during flight while the at least three liftingpropellers of the left linear support and the at least three liftingpropellers of the right linear support remain entirely disposed on theoutside of the left and right linear supports, respectively; wherein theleft and right linear supports are spaced apart from the fuselage andare parallel to each other; placing a center of gravity of the drone ona center longitudinal location of the fuselage; and wherein one of theat least three lifting propellers disposed entirely on the outside ofthe left linear support is disposed on a top side of the left linearsupport, and another one of the at least three lifting propellersdisposed entirely on the outside of the left linear support is disposedon a bottom side of the left linear support.
 11. The method as recitedin claim 10, wherein said point CG is located at one third of a distancefrom a point B which is defined as a center of lift force between aforemost two lift propellers on the left linear support and a foremosttwo lift propellers on the right linear support to a point D which isdefined as a center of lift force between a rear most lift propeller onthe left linear support and a rearmost propeller on the right linearsupport.
 12. The method as recited in claim 11, wherein the left andright forewings and the left and right hind wings have no movable flightcontrol surfaces.
 13. The method as recited in claim 12, furthercomprising providing a push propeller on the drone to provide a force ofpropulsion.
 14. The method as recited in claim 12, wherein the foremosttwo lift propellers disposed on the left linear support partiallyoverlap in their ranges of movement from a top view.
 15. The method asrecited in claim 10, wherein the center of gravity is located at twothird of a distance from a point A which is defined as a center of liftforce between a foremost lift propeller on the left linear support and aforemost propeller on the right linear support to a point C which isdefined as a center of lift force between a rearmost two lift propellerson the left linear support and a rearmost two lift propellers on theright linear support.